In the past there have been various vehicle barriers placed directly across roadways to prevent vehicle penetration. One of the difficulties associated with such barriers is that the barrier must be removably placeable across a roadway. Thus, the barrier must be massive enough to arrest a vehicle, yet light enough to be removed for regular vehicular traffic. In order to provide the above-functions, light-weight barriers have been substituted for massive barriers. These light-weight barriers have required expensive and somewhat unreliable brakes or shock absorbing systems, so that the light-weight barrier will not break on impact. Such a system is illustrated in U.S. Pat. No. 4,576,507, in which a barrier is released to come down to attempt to stop a high speed vehicle. In this case, the barrier is prevented from breaking away by virtue of expensive or unyieldy spring loaded absorbers. By way of further background, in the past, various flexible rail road crossing gates and highway guard fences such as illustrated in U.S. Pat. Nos. 1,848,516; 1,848,517; 3,292,909 have also utilized various types of shock absorbing mechanisms which includes brakes on drums or other hydraulic and spring-loaded systems. These are likewise complicated and expensive. Note that yieldable barriers used for traffic include U.S. Pat. Nos. 2,295,205 and 1,828,296 which are also cable and drum type braking systems. Flexible impact barriers are illustrated, for example, by U.S. Pat. No. 4,645,375 and a device for arresting airplanes which includes a net that has a shock-absorbing device including a braking system is illustrated in U.S. Pat. No. 3,013,750. Finally, U.S. Pat. No. 1,748,563 illustrates a flexible obstruction device extending across an open driveway to prevent access by gradually bringing an automobile to a stop at a right-of-way, street, or other crossing. Means for providing a retarding force include the paying out of the cables connected to the obstructing device which includes a braking mechanisms to retard the paying out of the cable.